Chronic conditions strongly associated with physical inactivity Flashcards
What is the estimate for US adults with hypertension
77.9 million US adults >= 20 years of age and more than 1 billion world wide
Primary Hypertension…
What are the causes
Essential, Idiopathic
No definitive cause Genetic Alcohol Stress High fat diet High salt diet Physical inactivity Obesity
What does idiopathic mean
We dont know what caused the hypertension
Secondary Hypertension…
What are the causes
Develops through the manifestation of other medical problems
Genetic Renal Vascular Endocrine Over the counter medications
Pathophysiology of hypertension involves
High sympathetic nervous system activity
Structural narrowing of small arteries and arterioles
Reduction of capillaries
Arterial stiffness
Increased resistance to blood flow (TPR)
What detects a change in BP
Baroreceptors
Baroreceptors send a
Afferent signal to CNS
BP =
HR x SV x TPR
Cardiac output
HR x SV
What constricts to slow down and build resistance
Arteries and arterioles
What controls vasoconstriction
VSMC
Vascular smooth muscle cells
What are VSMC
Vascular smooth muscle cells
What are VSMC’s controlled by
Pre/post ganglion sympathetic neurones
What does pre ganglion sympathetic neurons release
What do post ganglion release
Acytle co enz
norephedrine
What has the overall control of BP
Kidneys
What is the special considerations for exercise and hypertension with those whose BP not controlled
Those whose BP not controlled (SBP >= 140 and/or DBP >= 90) should consult their physician prior to initiating an exercise program to determine if an exercise testing is needed
What is the special consideration for exercise and hypertension for individuals with SBP >=160 or DBP >=100 or with target organ disease
Must not engage in any exercise
No exercise testing prior to a medical evaluation and adequate BP management
Medically supervised symptom limited exercise test is recommended prior to engaging in an exercise program test
What do Beta Blockers do
Adverse effect on thermoregulatory function
Increase the hypoglycemia in certain individuals
Reduce submaximal and maximal exercise capacity primarily in patients without myocardial ischemia
Decreased submax and max HR
What do Antihypertensive medication such as alpha blockers, calcium channel blockers and vasodilators do
Sudden excessive reduction in post exercise BP = postexercise hypotension
Termination of the exercise should be gradual and the cool down period should be extended and carefully monitored until BP and HR return to near resting levels
What are beta blockers
What does it cause the heart to do
Target beta receptors in heart which stops NE and Ephedrine from binding and exciting the heart
Therefore slows down heart rate
Mechanism of Digoxin
Slows HR at atria to ventricle
Inhibition of sodium potassium adenosine triphosphatase
Mechanism of betablockers
Slow HR
Antagonists that block the receptor sites for Epi and NE on adrenergic beta receptors of SNS
Mechanism of calcium channel blockers
Slow HR
Reduce strength of cardiac muscle contraction
Prevent or reduce the opening of channels, not allowing Ca++ to get into cells
Mechanism of alpha blockers
Relax vascular smooth muscle cells, vasodilate
Reduce vascular resistance
Increase blood flow
A lack of calcium causes
Actin to not be exposed
Causes weaker contraction
What are the effects of exercise on hypertension
Average reduction of 5 to 10 mmHg in resting BP
Potential alterations:
Alteration in renal function
Decrease in plasma norepinephrine
Increase in circulating vasodilator substances
FITT recommendation for individuals with hypertension and AEROBIC
5-7 days
Moderate intensity
> = 30 min of continuous
Intermittent for 10 min bouts
Prolonged activities using large muscles